added initial oracle storage and price calc

Author: ShivaanshK

contracts/common/BiconomyTokenPaymasterErrors.sol

@@ -31,4 +31,14 @@ contract BiconomyTokenPaymasterErrors {
      * @notice Throws when invalid signature length in paymasterAndData
      */
     error InvalidDynamicAdjustment();
+
+    /**
+     * @notice Throws when each token doesnt have a corresponding oracle
+     */
+    error TokensAndOraclesLengthMismatch();
+
+    /**
+     * @notice Throws when oracle returns invalid price
+     */
+    error OraclePriceNotPositive();
 }

contracts/interfaces/IBiconomySponsorshipPaymaster.sol

@@ -6,7 +6,7 @@ import { PackedUserOperation } from "@account-abstraction/contracts/core/UserOpe
 
 interface IBiconomySponsorshipPaymaster{
     event UnaccountedGasChanged(uint256 indexed oldValue, uint256 indexed newValue);
-    event FixedDynamicAdjustmentChanged(uint32 indexed oldValue, uint32 indexed newValue);
+    event FixedDynamicAdjustmentChanged(uint256 indexed oldValue, uint256 indexed newValue);
     event VerifyingSignerChanged(address indexed oldSigner, address indexed newSigner, address indexed actor);
     event FeeCollectorChanged(address indexed oldFeeCollector, address indexed newFeeCollector, address indexed actor);
     event GasDeposited(address indexed paymasterId, uint256 indexed value);
@@ -22,7 +22,7 @@ interface IBiconomySponsorshipPaymaster{
 
     function setFeeCollector(address _newFeeCollector) external payable;
 
-    function setUnaccountedGas(uint16 value) external payable;
+    function setUnaccountedGas(uint256 value) external payable;
 
     function withdrawERC20(IERC20 token, address target, uint256 amount) external;
 

contracts/interfaces/IBiconomyTokenPaymaster.sol

@@ -3,7 +3,7 @@ pragma solidity ^0.8.26;
 
 interface IBiconomyTokenPaymaster {
     event UnaccountedGasChanged(uint256 indexed oldValue, uint256 indexed newValue);
-    event FixedDynamicAdjustmentChanged(uint32 indexed oldValue, uint32 indexed newValue);
+    event FixedDynamicAdjustmentChanged(uint256 indexed oldValue, uint256 indexed newValue);
     event FeeCollectorChanged(address indexed oldFeeCollector, address indexed newFeeCollector, address indexed actor);
     event GasDeposited(address indexed paymasterId, uint256 indexed value);
     event GasWithdrawn(address indexed paymasterId, address indexed to, uint256 indexed value);

contracts/interfaces/oracles/IOracle.sol

@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+interface IOracle {
+    function decimals() external view returns (uint8);
+    function latestRoundData()
+        external
+        view
+        returns (uint80 roundId, int256 answer, uint256 startedAt, uint256 updatedAt, uint80 answeredInRound);
+}

contracts/sponsorship/BiconomySponsorshipPaymaster.sol

@@ -40,13 +40,14 @@ contract BiconomySponsorshipPaymaster is
 
     address public verifyingSigner;
     address public feeCollector;
-    uint16 public unaccountedGas;
-    uint32 private constant PRICE_DENOMINATOR = 1e6;
+    uint256 public unaccountedGas;
 
+    // Denominator to prevent precision errors when applying dynamic adjustment
+    uint256 private constant PRICE_DENOMINATOR = 1e6;
     // Offset in PaymasterAndData to get to PAYMASTER_ID_OFFSET
     uint256 private constant PAYMASTER_ID_OFFSET = PAYMASTER_DATA_OFFSET;
     // Limit for unaccounted gas cost
-    uint16 private constant UNACCOUNTED_GAS_LIMIT = 50_000;
+    uint256 private constant UNACCOUNTED_GAS_LIMIT = 50_000;
 
     mapping(address => uint256) public paymasterIdBalances;
 
@@ -55,7 +56,7 @@ contract BiconomySponsorshipPaymaster is
         IEntryPoint _entryPoint,
         address _verifyingSigner,
         address _feeCollector,
-        uint16 _unaccountedGas
+        uint256 _unaccountedGas
     )
         BasePaymaster(_owner, _entryPoint)
     {
@@ -123,11 +124,11 @@ contract BiconomySponsorshipPaymaster is
      * @param value The new value to be set as the unaccountedEPGasOverhead.
      * @notice only to be called by the owner of the contract.
      */
-    function setUnaccountedGas(uint16 value) external payable override onlyOwner {
+    function setUnaccountedGas(uint256 value) external payable override onlyOwner {
         if (value > UNACCOUNTED_GAS_LIMIT) {
             revert UnaccountedGasTooHigh();
         }
-        uint16 oldValue = unaccountedGas;
+        uint256 oldValue = unaccountedGas;
         unaccountedGas = value;
         emit UnaccountedGasChanged(oldValue, value);
     }
@@ -346,7 +347,7 @@ contract BiconomySponsorshipPaymaster is
     function _checkConstructorArgs(
         address _verifyingSigner,
         address _feeCollector,
-        uint16 _unaccountedGas
+        uint256 _unaccountedGas
     )
         internal
         view

contracts/token/BiconomyTokenPaymaster.sol

@@ -4,11 +4,12 @@ pragma solidity ^0.8.26;
 import { ReentrancyGuardTransient } from "@openzeppelin/contracts/utils/ReentrancyGuardTransient.sol";
 import { IEntryPoint } from "@account-abstraction/contracts/interfaces/IEntryPoint.sol";
 import { PackedUserOperation, UserOperationLib } from "@account-abstraction/contracts/core/UserOperationLib.sol";
-import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import { IERC20, ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 import { SafeTransferLib } from "@solady/src/utils/SafeTransferLib.sol";
 import { BasePaymaster } from "../base/BasePaymaster.sol";
 import { BiconomyTokenPaymasterErrors } from "../common/BiconomyTokenPaymasterErrors.sol";
 import { IBiconomyTokenPaymaster } from "../interfaces/IBiconomyTokenPaymaster.sol";
+import { IOracle } from "../interfaces/oracles/IOracle.sol";
 import "@account-abstraction/contracts/core/Helpers.sol";
 
 /**
@@ -29,9 +30,17 @@ contract BiconomyTokenPaymaster is
 {
     using UserOperationLib for PackedUserOperation;
 
+    struct TokenInfo {
+        IOracle oracle;
+        uint8 decimals;
+    }
+
+    // State variables
     address public feeCollector;
     uint256 public unaccountedGas;
     uint256 public dynamicAdjustment;
+    IOracle public nativeOracle; // ETH -> USD price
+    mapping(address => TokenInfo) tokenDirectory;
 
     // Limit for unaccounted gas cost
     uint256 private constant UNACCOUNTED_GAS_LIMIT = 50_000;
@@ -42,19 +51,30 @@ contract BiconomyTokenPaymaster is
         address _owner,
         IEntryPoint _entryPoint,
         uint256 _unaccountedGas,
-        uint256 _dynamicAdjustment
+        uint256 _dynamicAdjustment,
+        IOracle _nativeOracle,
+        address[] memory _tokens, // Array of token addresses
+        IOracle[] memory _oracles // Array of corresponding oracle addresses
     )
         BasePaymaster(_owner, _entryPoint)
     {
         if (_unaccountedGas > UNACCOUNTED_GAS_LIMIT) {
             revert UnaccountedGasTooHigh();
         } else if (_dynamicAdjustment > MAX_DYNAMIC_ADJUSTMENT || _dynamicAdjustment == 0) {
             revert InvalidDynamicAdjustment();
+        } else if (_tokens.length != _oracles.length) {
+            revert TokensAndOraclesLengthMismatch();
         }
         assembly ("memory-safe") {
             sstore(feeCollector.slot, address()) // initialize fee collector to this contract
             sstore(unaccountedGas.slot, _unaccountedGas)
             sstore(dynamicAdjustment.slot, _dynamicAdjustment)
+            sstore(nativeOracle.slot, _nativeOracle)
+        }
+
+        // Populate the tokenToOracle mapping
+        for (uint256 i = 0; i < _tokens.length; i++) {
+            tokenDirectory[_tokens[i]] = TokenInfo(_oracles[i], ERC20(_tokens[i]).decimals());
         }
     }
 
@@ -211,8 +231,7 @@ contract BiconomyTokenPaymaster is
         override
         returns (bytes memory context, uint256 validationData)
     {
-        (maxCost);
-        // Implementation of post-operation logic
+        
     }
 
     /**
@@ -239,4 +258,30 @@ contract BiconomyTokenPaymaster is
         if (target == address(0)) revert CanNotWithdrawToZeroAddress();
         SafeTransferLib.safeTransfer(address(token), target, amount);
     }
+
+    /// @notice Fetches the latest token price.
+
+    /// @return price The latest token price fetched from the oracles.
+    function getPrice(address tokenAddress) internal view returns (uint192) {
+        TokenInfo memory tokenInfo = tokenDirectory[tokenAddress];
+        uint192 tokenPrice = _fetchPrice(tokenInfo.oracle);
+        uint192 nativeAssetPrice = _fetchPrice(nativeOracle);
+        uint192 price = nativeAssetPrice * uint192(tokenInfo.decimals) / tokenPrice;
+        return price;
+    }
+
+    /// @notice Fetches the latest price from the given oracle.
+    /// @dev This function is used to get the latest price from the tokenOracle or nativeAssetOracle.
+    /// @param _oracle The oracle contract to fetch the price from.
+    /// @return price The latest price fetched from the oracle.
+    function _fetchPrice(IOracle _oracle) internal view returns (uint192 price) {
+        (, int256 answer,, uint256 updatedAt,) = _oracle.latestRoundData();
+        if (answer <= 0) {
+            revert OraclePriceNotPositive();
+        }
+        // if (updatedAt < block.timestamp - stalenessThreshold) {
+        //     revert OraclePriceStale();
+        // }
+        price = uint192(int192(answer));
+    }
 }

contracts/token/oracles/TwapOracle.sol

@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.23;
+
+import {IOracle} from "../../interfaces/oracles/IOracle.sol";
+import {IERC20Metadata} from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
+import {OracleLibrary} from "@uniswap/v3-periphery/contracts/libraries/OracleLibrary.sol";
+import {IUniswapV3PoolImmutables} from "@uniswap/v3-core/contracts/interfaces/pool/IUniswapV3PoolImmutables.sol";
+
+
+contract TwapOracle is IOracle {
+    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
+    /*                       CUSTOM ERRORS                        */
+    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
+    /// @dev Invalid TWAP age, either too low or too high
+    error InvalidTwapAge();
+
+    /// @dev Pool doesn't contain the base token
+    error InvalidTokenOrPool();
+
+    /*´:°•.°+.*•´.*:˚.°*.˚•´.°:°•.°•.*•´.*:˚.°*.˚•´.°:°•.°+.*•´.*:*/
+    /*                  CONSTANTS AND IMMUTABLES                  */
+    /*.•°:°.´+˚.*°.˚:*.´•*.+°.•°:´*.´•*.•°.•°:°.´:•˚°.*°.˚:*.´+°.•*/
+    /// @dev The Uniswap V3 pool address
+    address public immutable pool;
+
+    /// @dev The base token address (the one which price is being fetched)
+    address public immutable baseToken;
+
+    /// @dev The base token decimals
+    uint256 public immutable baseTokenDecimals;
+
+    /// @dev The quote token address (WETH or USD stable coin)
+    address public immutable quoteToken;
+
+    /// @dev The quote token decimals
+    uint256 public immutable quoteTokenDecimals;
+
+    /// @dev Default TWAP age, used to fetch the price
+    uint32 public immutable twapAge;
+
+    uint32 public constant MINIMUM_TWAP_AGE = 1 minutes;
+    uint32 public constant MAXIMUM_TWAP_AGE = 7 days;
+
+    uint256 public constant ORACLE_DECIMALS = 1e8;
+
+    constructor(
+        address _pool,
+        uint32 _twapAge,
+        address _baseToken
+    ) {
+        pool = _pool;
+
+        if (_twapAge < MINIMUM_TWAP_AGE || _twapAge > MAXIMUM_TWAP_AGE) revert InvalidTwapAge();
+        twapAge = _twapAge;
+
+        address token0 = IUniswapV3PoolImmutables(_pool).token0();
+        address token1 = IUniswapV3PoolImmutables(_pool).token1();
+
+        if (_baseToken != token0 && _baseToken != token1) revert InvalidTokenOrPool();
+
+        baseToken = _baseToken;
+        baseTokenDecimals = 10 ** IERC20Metadata(baseToken).decimals();
+
+        quoteToken = token0 == baseToken ? token1 : token0;
+        quoteTokenDecimals = 10 ** IERC20Metadata(quoteToken).decimals();
+    }
+
+    function decimals() external override pure returns (uint8) {
+        return 8;
+    }
+
+    function latestRoundData() external override view returns (
+        uint80 roundId,
+        int256 answer,
+        uint256 startedAt,
+        uint256 updatedAt,
+        uint80 answeredInRound
+    ) {
+        uint256 _price = _fetchTwap();
+
+        // Normalize the price to the oracle decimals
+        uint256 price = _price * ORACLE_DECIMALS / quoteTokenDecimals;
+
+        return _buildLatestRoundData(price);
+    }
+
+    function _buildLatestRoundData(uint256 price) internal view returns (
+        uint80 roundId,
+        int256 answer,
+        uint256 startedAt,
+        uint256 updatedAt,
+        uint80 answeredInRound
+    ) {
+        return (0, int256(price), 0, block.timestamp, 0);
+    }
+
+    function _fetchTwap() internal view returns (uint256) {
+        (int24 arithmeticMeanTick,) = OracleLibrary.consult(pool, twapAge);
+
+        return OracleLibrary.getQuoteAtTick(
+            arithmeticMeanTick,
+            uint128(baseTokenDecimals), // Base token amount is equal to 1 token
+            baseToken,
+            quoteToken
+        );
+    }
+}

lib/v3-core

@@ -129,14 +129,14 @@ contract TestSponsorshipPaymasterWithDynamicAdjustment is TestBase {
     }
 
     function test_SetUnaccountedGas() external prankModifier(PAYMASTER_OWNER.addr) {
-        uint16 initialUnaccountedGas = bicoPaymaster.unaccountedGas();
-        uint16 newUnaccountedGas = 5000;
+        uint256 initialUnaccountedGas = bicoPaymaster.unaccountedGas();
+        uint256 newUnaccountedGas = 5000;
 
         vm.expectEmit(true, true, false, true, address(bicoPaymaster));
         emit IBiconomySponsorshipPaymaster.UnaccountedGasChanged(initialUnaccountedGas, newUnaccountedGas);
         bicoPaymaster.setUnaccountedGas(newUnaccountedGas);
 
-        uint48 resultingUnaccountedGas = bicoPaymaster.unaccountedGas();
+        uint256 resultingUnaccountedGas = bicoPaymaster.unaccountedGas();
         assertEq(resultingUnaccountedGas, newUnaccountedGas);
     }